<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <script src="./vue.js"></script>
</head>

<body>
    <div id="app">
        <div v-if="flag">{{msg}}</div>
        <div v-else>你好</div>
    </div>
    <script>
        new Vue({
            el: "#app",
            data: {
                flag: true,
                msg: "hello world"
            },
            methods: {
                isshow() {
                    setTimeout(() => {
                        this.flag = false
                    }, 2000)
                }
            },
        })
    </script>
</body>

</html>